Air traveler&#39;s rest period calculator

ABSTRACT

A device are described for calculating the periods of rest necessary for the physical and mental well-being of an air traveler after long-distance flights. The device is basically a pocket-sized calculator consisting of two concentric discs and a pointer. The larger disc is subdivided in an outer and an inner ring. The outer ring is marked in 10 and 5 degree intervals which indicate the travel time in hours and half-hours, respectively. The center ring is marked to show the duration of the rest period in hours. The smaller disc bears the scales of the additional five parameters which determine the length of the rest period. The overlaying pointer, which can be rotated about the center of the device, provides for the reference setting of each parameter, for their summation, and for the reading of the final result.

United States Patent Gerathewohl [54]- AIR TRAVELER'S REST PERIODCALCULATOR [72] Inventor: Siegfried Johannes Gerathewohl, 5208 AlbemarleSt., Bethesda, Md.

[22] Filed: Aug. ll, 1970 [2l] Appl. No.: 62,959

[52] U.s. cl 23S/88 [5 l] Int. Cl. G04b 37/00 [58] Field of Search.....238/78, 88

[56] References Cited i l UNITED STATES PATENTS 2,418,933 4/1947 Hill..235/78 2,694,522 ll/1954 Sturgeu et al ..235/88 3,232,253 2/1966Hodge, Jr ..235/78 X 3,253,780 5/1966 Stewart et al .,235/78 [1s-13,681,572 [451 Aug. 1,1972

Primary Examiner-Richard B. Wilkinson Assistant Examiner-Stanley A. Wal

[57] ABSTRACT A device are described 'for calculating the periods ofrest necessary for the physical and mental well-being of an air travelerafter long-distance flights. The device is basically a pocketfsizedcalculator consisting of two concentric discs and a pointer. The largerdisc issubdivided in an outer and an inner ring. The outer ring 'ismarked in l0 and 5 degree intervals which in dicate the travel time inhours and half-hours, respectively. The center ring is marked to showthe duration of the rest period in hours. The smaller disc bears thescales of the additional five parameters which determine the length ofthe rest period. The overlaying pointer, which can be rotated about thecenter of the device, provides for. the reference setting of eachparameter, for their summation, and for the reading of the final result.

l Claim, 2 Drawing Figures P'A'TENTEDAUS' 1 |912 l N VENTOR. SIEGFRI EDJOHANNES GERATHEWOHL AIR TRAVELERS REST PERIOD CALCULATOR BACKGROUND OETHE INVENTION The effects of long-distance journeys on the physiologicaland mental functions. of the traveler became' a matter of scientificstudy after the realization of modern air travel and global flights. Theexperiences of the traveler are compounded in the so-called jetflightstress Syndrom, which generally is a feeling of tiredness, fatigue,listlessness or irritation associated with sleeplessness, lack ofappetite, interest, initiative and activity shortly after arrival. Thissyndrom not only deprives the traveler of his enjoyment of the trip andhis sojourn at the point of destination, but also detrimentally affectshis behavior, the conduct of lhis business, andthe performance of hisduties. It has been voiced by experts on this subject that thiscenturyvhas witnessed out-of-character behavior and inept decisions atthe highest level of authority by persons who were not aware of theinadequate adaptation of their organism to the new environment. Amultitude of scientific investigations were therefore conducted duringthe past ten years which demonstrated quantitatively the performancedecrement of test subjects, passengers, and crews after actual orsimulated long-distance flights.

What are the main parameters which affect the physical and mental stateof the jet-age traveler? A travelers physical and mental state after alongdistance flight is generally influenced by (l) personal factors,such as emotional and health status, age, motivation, and adaptability;(2) geographic and environmental factors, such as climate, departure,and arrival time; geographic translocation; and the associated time-zoneshifts, altitude, and accommodations; and (3) operational factors, suchas duration of flight, flying speed, and number of stops or stays on theground. In 1967 a formula was proposed by the Staff Advisory Committeeof the International Civil Aviation Organization (ICAO), in which fourof these factors were used for computing a physiological rest periodafter long flights. The formula was:

Rest period (in tenth .of a day) Flight duration (in hours)/2 Number oftime zones in excess of 4 Departure time coefficient -l- Arrival timecoefficient.

Although this formula has been used by some individuals andorganizations to compute rest periods after long flights, it was notadopted by the United Na tions for common practice. There are severalshortcomings of the ICAO formula:`

l. The ICAO formula does not include the bidirectional factor which isimportant in case of East West and West-East dislocations.

2. The I CAO formula does not include the physiological time-zone shiftsassociated with longitudinal changes of less than 75. However, theseshifts must be Y physiologic rest periods after long-distance flights, a

considered already in case of U.S. transcontinental new formula wastherefore developed by the inventor which includes the age andgeodirectional factors, expands the local departure and arrival timecoefficients, and realistically considers relatively small time-zonechanges to benefit the traveler. The new formula reads:

Rest period Travel time in hours -l- Departure time coefficient Numberof time zones Arrival time coeicient Geodirectional coefficient Agecoefficient, or

RP=T+DC+TZ+AC+GC+A- This formula is scientifically more accurate, easierto apply than the old formula because hours are used for input andoutput, and its results are in close approximation but more reasonablethan those of the former. l

SUMMARY OF THE INVENTION This invention concerns the attenuation ofphysical and mental effects of long-distance flights'. It is based on anew formula to be used for calculating physiological rest periods tocombat jet-flight fatigue. The Air Traveler Restometer, which is thesubject of this invention, enables the traveler to compute the restperiod following the trip immediately, quickly, without difficulty, andwithout supporting material and assistance. This period is recommendedby physicians and scientists as a minimum in order that the travelerwill be in the best physical and mental condition to enjoy his stay atthe place of arrival or take care of his business and optimally performhis d uties. The calculations are based on the latest scientific dataconcerning the desynchronization of biological functions and otherstress factors associated with jet travel and time-zone fatigue.

Another objective of this invention is to furnish a rest periodcalculator which is simple and inexpensive to manufacture, easy to carryalong, quick to use, reliable and durable in operation, and can be madeavailable to a large segment of the traveling public.

Another objective of this invention is to make practical use of a newand accurate formula for the benefit of people who are on pleasure or onbusiness trips so that they can get the maximum return and avoid costlyerrors or failures in business as well as improper decisions in officialor political matters.

Another objective of the invention is to help private, military, andairline pilots and crews to properly plan non-scheduled and scheduledflights in order to avoid aircraft accidents owing to `insufficientrecreation, sleep, and rest periods. l

Another objective of this invention is to provide to the military,technical, and political officers, or-

ganizers, and leaders a practical and useful tool for onthe-spotcalculations of respective personnel, manpower, and efforts or resourcesavailable for alert, combat, and emergency conditions afterlone-distance air transports or air evacuations.

Another objective of this invention is to provide a rest periodcalculator, which can be supplemented by adding other related features,such as pictorial displays of the shift of the diurnal. cycle andphysiological profiles resulting from the geodirectional displacement ofthe traveler.

The six factors travel time, number of time zones, departure time,arrival time, direction of flight, and age are significantly related tothe physiological rest period. Itis a well-known fact that length oftravel alone'is so stressfulduring long-distance flights that a lto-lhour relationship between -flight duration and rest period has beenaccepted for air carrier operations. While the ICAO formula weighstime-zone shifts in excess of 4 equally with travel, departure, andarrival times, the new formula developed bythe inventor considerstime-zone shifts from l to l2 hours in accordance with the newestscientific data. Cycles of sleep-wakefulness, oral temperature,psychomotor function, and renal excretions of 17-Ol-I corticosteroids,l7-corticosteroids, sodium and potassium were studied in healthysubjects during West-East and East- West displacements, and theirdesynchronization curves were plotted over the 36-hour travel, resultingin a sector of approximately 150 as shown in FIG. l. The relationship ofthe stepwise increments of this scale to rest period is in agreementwith the original expermental results.

For example, a rest period of 9 hours is allowed by the- ICAO formulaafter a flight from Montreal, Canada, to Sidney, Australia, because oftime-zone shifts alone; and a l-hour rest period will account for thetime-zone shift in traveling half-way around the world.

The weights of the departure and arrival time factors are in closeapproximation to that of the ICAO formula, which has yielded the desiredresults. The increased weighting given the later hours for departurehelps to compensate for the effects of loss of sleep. Also, the higharrival time coefficient for the period 0800 to i ll59 helps tocompensate for the disruption experienced during early-morning flightsplus the effect of arriving at the beginning of a workday withoutsufficient rephasing of the diurnal rhythm. The sizes of the sectors orincrements on the scale of the Restometer were obtained by a geometrictransformation of the accepted ICAO values.

Recent research has clearly indicated the longer adjustment time ofpsychophysiologic functions necessary after West-East displacement.Mathematically, the scales of the bidirectional coefficient are asupplement to the time-zone factors, and their size was experimentallydetermined. Since readjustment after West-to- East flights was found totake almost twice as long as after flights in the East-West direction,twice as many rest hours are allowed after West-East flights than viceversa.

Finally, the size of the age allowances on the scale were empiricallyestablished. Recent studies on aging` have shown that adjustment to newsituations and unknown conditions is not as rapid after age 40. Thescale values on the device were affixed accordingly.

The advantages and merit of the invention will become apparent with thefollowing description and display ofthe device, wherein:

FIG. ll is a plain view of the vRestometer in accordance with thisinvention; I

FIG. 2` is a cross-sectional `view of the Restometer shown in FIG. l.

DESCRIPTION oF THE PREFERRED EMBODIMENTS -large disc is subdivided intoan outer ring 5 and an inner ring 6. The outer ring is marked in 10 and5 intervals, carrying the numbers from l to 36 which indicate the numberof hours spent in travel. This scale'is therefore marked as Air'TravelTime in Hours. The center ring, which is part of the large disc,is'marked in l0 intervals carrying the numbers from l to 72 on a doublescale. This scale shows the Rest Period in Hours. The smaller disc,which is transparent in its center to allow for the reading of the restperiod, bears the rest period namely, the local departure-timecoefficient 7, the directional coefficient 8, the number of time zonescrossed 9, the local arrival time coefficient l0, and the agecoefficient ll. Specifically, the parameters are scaled as follows: thedeparture-time coefficient and the arrival-time coefficient are weighedin accordance with the diurnal performance as determined by scientificyexperiments conducted on pilots and non-pilot populations. Thetime-zone scale is graded as a cyclic function in accordance withcircadian adjustment to local time after geographic dislocation. Thegeodirectional coefficient is weighed differently for West-to-East andEast-to-West flights, since the circadian acrophase adjustment afterWest- East flights is slower than after East-West dislocation. Hence,traveling from West to East contributes twice as many credit points tothe rest period than traveling from East to West. Finally, the agecoefficient is weighed so'that older persons get more credit afterlong-distance flights than younger ones.

In order to.calculate the recommended period of rest, the pointer 12 isset at the zero mark of the Air Travel Time in Hours scale and thenmoved tothe number indicating the number of hours traveled, for example,7. Next, the zero point (left border) of the dep'arture-time coefficientis placed under the hairline of the pointer and the pointer then movedin the clockwise direction until if the local time of departure happenedto be 10:00 p.m. or 2,200 it indicates the 4 credit points allowed forthis late departure time. This adds up to ll hours of credit. Next thezero point of the time-zone scale isplaced under the hairline, and

the number of time zones crossed, for example, 6, is

added by moving the pointer'again in the clockwise direction adding upto 15.5. Next the local arrival time coefficient is added by againsetting the zero position under the hairline and then moving the pointerclockwise to 5 if the plane happens to arrive at 8:30 a.m. or 0830 localtime, which is a bad time for catching up on sleep. This now amounts to20.5 hours credit. Since this was a West-to-East flight, the traveler isentitled to 2 directional credits. Again the zero position of theWest-East scale is placed under the hairline and the pointer then movedto indicate the 2. The credit hours are now 22.5. Lastly, the agecoefficient, for example, 2, is added by following the now-familiarprocedure. In this way, a total of 25 hours is obtained, this totalbeing shown on the center scale. Thisis the physiological rest periodrecommended to the traveler after a night-flight from New York toLondon.

Since several different embodiments of this invention may be madewithout departing from the principle and scope thereof, it is to beunderstood that the specific embodiment described in detail herein isnot be be taken in a limiting sense.

I claim:

1. A disc-shaped calculator for determining physiologically-requiredrest periods after longdistance flights involving time-zone shifts. Thisdevice comprisesa. a circular baseplate carrying reference markingsindicating air-travel time in hours and rest period in hours marked in 5and 10 intervals about the circumferences of an inner and an outer ringseparated by an empty ring, the inner ring having a double scale forrest periods up to 72 hours, given in numbers from l to 72;

b. a transparent, circular plate of smaller size than the baseplateoverlying it and attached at its center to permit rotational movement;subdivided into five major sectors carrying the indicia of the fivecritical factors number of time zones crossed, arrival-time coefficient,East-West/West-East coefficient, age coeicient, and departure-timecoefficient clockwise in this order; filling the interspace between theinner and outer rings of the base plate; and having a predeterminedrelation to said first-reference markings; t

c. a transparent cursor member overlying the two circular plates,extending in radius slightly'over the baseplate for easy rotation andcarrying a center hairline indicator which can be set on the respectiveindicia on the outer ring and the smaller disc carrying said criticalfactors or coefficients for calculating rest periods, thus relating thetravel time, time-zone shifts, and departure-time, arrival-time,bidirectional, and age coeicients to the rest period as shown on thescale of the inner ring; and

v d. means for holding the two discs and the cursor together forrotating about a common axis, the described arrangement making itpossible for the smaller disc and the cursor to be rotated independentlyof each other so that the said relationship of the indicia of the threecircular scales can be obtained.

1. A disc-shaped calculator for determining physiologicallyrequired restperiods after long-distance flights involving timezone shifts. Thisdevice comprisesa. a circular baseplate carrying reference markingsindicating air-travel time in hours and rest period in hours marked in5* and 10* intervals about the circumferences of an inner and an outerring separated by an empty ring, the inner ring having a double scalefor rest periods up to 72 hours, given in numbers from 1 to 72; b. atransparent, circular plate of smaller size than the baseplate overlyingit and attached at its center to permit rotational movement; subdividedinto five major sectors carrying the indicia of the five criticalfactors - number of time zones crossed, arrival-time coefficient,East-West/WestEast coefficient, age coefficient, and departure-timecoefficient clockwise in this order; filling the interspace between theinner and outer rings of the base plate; and having a predeterminedrelation to said first-reference markings; c. a transparent cursormember overlying the two circular plates, extending in radius slightlyover the baseplate for easy rotation and carrying a center hairlineindicator which can be set on the respective indicia on the outer ringand the smaller disc carrying said critical factors or coefficients forcalculating rest periods, thus relating the travel time, timezoneshifts, and departure-time, arrival-time, bidirectional, and agecoefficients to the rest period as shown on the scale of the inner ring;and d. means for holding the two discs and the cursor together forrotating about a common axis, the described arrangement making itpossible for the smaller disc and the cursor to be rotated independentlyof each other so that the said relationship of the indicia of the threecircular scales can be obtained.